Microbiological Considerations for Probiotic Supplemented Foods SciDoc Publishers | Open Access | Science Journals | Media Partners

For exhibiting prophylactic properties, cultured milk products must retain sufficient population of viable organisms throughout its anticipated shelf-life. Ingestion of acidophilus milk containing 3x107cells/ml L. acidophilus for 30 day induced a fall in blood serum cholesterol level in human volunteers [18]. Ingestion of yoghurt containing 108 cfu/g B. longum [19] and hydrolyzed whey formulae containing 1x109 cfu/g B. lactis [20] induced significant reduction in total serum cholesterol in humans and modify infant’s gut microbiota, thereby alleviating allergic inflammation. An elevation in bifidobacteria counts as well as a decline in enterobacteria in mice cherishing bifidus milk containing 107 cells of B. longum for 14 days was noted [21]. Animal and infant feeding trials revealed a decline in coliforms and an increment in faecal bifidobacteria and/or lactobacilli due to ingestion of bifidus milk [22], Propiono-Acido-Bifido [PAB] milk [23, 24] and dietetic yoghurt [25] containing B. bifidum [108 cfu/ml]. Ingestion of fermented milk containing 5x107 cfu/ml L. acidophilus and L. casei by human volunteers [26] or bifidus milk containing 108 cfu/g B. bifidum by infants [22] induced an elevation in faecal lactobacilli [7.59-8.93 log cfu/ml] and bifidobacteria (2.2x108-19.8x108cfu/g), respectively. Lactobacilli supplemented in milk at a level of 109 viable/day [27] or 1011 cfu/day [28, 29] were efficacious in reducing the faecal β-glucuronidase and β-glucosidase activity in human subjects responsible for carcinogenesis. Decline in nitroreductase activity during ingestion and its retention at a low level after cessation of intake of fermented milk product containing L. acidophilus [107 cfu/g], B. bifidum ([108 cfu/g) and Lactococcus lactis (108 cfu/g) and Lactococcus lactis subsp. cremoris (108 cfu/g) were noted [30]. An improvement in lactose digestion due to ingestion of milk supplemented with L. acidophilus (2.5x106 to 2.5x10,8cfu/ml) was observed [31]. Human trials revealed lowest breath hydrogen (9.9, 22.8, 50.2 ppm) due to ingestion of cultured yoghurt in contrast to heated cultured yoghurt or direct acid yoghurt, respectively [32]. Decrement in viable population (3x108/g to 3.4x106/g) and lactase activity (0.64 to 0.07 units/g) due to pasteurization [33] and better tolerance of non-pasteurized yoghurt than pasteurized yoghurt by lactase-non-persistent individuals [34, 35] indicate sigS. Sarkar, International Journal of Microbiology & Advanced Immunology 2013, 1:102 3 nificance of viable population. It has been established that to achieve health